2015 Japanese Society for Dialysis Therapy: Guidelines for Renal Anemia in Chronic Kidney Disease

Prevalence and relevance of cachexia as diagnosed by two different definitions in patients undergoing hemodialysis: A retrospective and exploratory study

OBJECTIVE

Cachexia is present in various chronic diseases and is associated with decreased quality of life and increased risk of morbidity and mortality. However, evidence regarding the association of cachexia with prognosis in patients undergoing hemodialysis is limited. We assessed cachexia using two definitions and compared prevalence, functional impairment, and prognostic impact in patients undergoing hemodialysis.

METHODS

We enrolled outpatients undergoing hemodialysis at two centers retrospectively. We assessed cachexia using the conventional cachexia (Evans' criteria) and the Asian Working Group for Cachexia (AWGC) criteria. The study examined all-cause mortality and functional status (Clinical Frailty Scale and short physical performance battery). We used Cox proportional hazards model to examine the association with prognosis, and logistic regression analysis to examine the association with functional impairment.

RESULTS

Among 367 patients (mean age, 67 years; 63 % male), cachexia prevalence, as defined by Evans' criteria and AWGC, was 21.3 % and 35.2 %, respectively. Cachexia as defined by Evans' criteria was associated with an increased risk of all-cause mortality (hazard ratio [HR], 95 % confidence interval [CI]: 1.81, 1.02-3.23). Also, cachexia as defined by AWGC criteria showed suggestive association with increasing mortality (HR, 95 % CI: 1.56, 0.90-2.70). Similar results were seen between cachexia and functional impairment.

CONCLUSIONS

Among patients on hemodialysis, cachexia was highly prevalent and was associated with poor prognosis and functional impairment. Detecting cachexia in earlier stages may be useful for risk stratification in this population.

Management of anaemia and prognosis of patients undergoing maintenance peritoneal dialysis: A nationwide cohort study

BACKGROUND

Clinical data supporting the target haemoglobin range in patients undergoing peritoneal dialysis (PD) are scarce. This study investigated the association between haemoglobin levels and all-cause mortality in Japanese patients undergoing PD using data from a nationwide dialysis registry.

METHODS

A total of 4875 patients aged ≥18 years who were undergoing PD at the end of 2012 were analysed. Patients receiving combination therapy with haemodialysis or missing haemoglobin data were excluded. Haemoglobin values were categorised into six groups (<9.0, 9.0-9.9, 10.0-10.9, 11.0-11.9, 12.0-12.9 and ≥13.0 g/dL) and their association with mortality evaluated.

RESULTS

Patients' mean age was 63 years, and 62% were men. The mean haemoglobin level was 10.7 g/dL, and 14% were anuric. Erythropoiesis-stimulating agents were used in 89%. During a median follow-up of 3.5 years, 1586 patients died. Haemoglobin levels <9.0 and ≥13.0 g/dL were significantly associated with mortality, as compared with levels of 10.0-10.9 g/dL (adjusted hazard ratios [95% confidence intervals]: 1.25 [1.06-1.48] and 1.45 [1.13-1.88], respectively). Restricted cubic spline analysis revealed a U-shaped association between haemoglobin levels and mortality. A haemoglobin level ≥12 g/dL was associated with mortality in patients with a history of cardiovascular disease (p interaction = 0.023).

CONCLUSION

We provide important insights into the target haemoglobin in patients undergoing PD. Our findings suggest that setting a lower upper limit for haemoglobin levels may be beneficial for patients with a history of cardiovascular disease.

Clinical management of iron deficiency anemia in Japan: iron prescription patterns, treatment effectiveness, and assessments

Iron deficiency anemia is one of the most common types of anemia, but real-world clinical management practices in Japan are unclear. This study retrospectively explored iron prescription patterns, treatment effectiveness, and assessments. Patients with at least one treatment period between September 2020 and September 2022 were included and classified into three groups (ferric carboxymaltose [FCM]: 7437 patients, saccharated ferric oxide [SFO]: 98,648 patients, and oral iron: 359,547 patients). Iron-related laboratory values over time and testing proportions were evaluated. Median baseline hemoglobin levels were lowest with FCM (FCM: 8.10 g/dL, SFO: 8.70 g/dL, oral iron: 9.70 g/dL), but changes in hemoglobin levels by 12 weeks were greatest with FCM (FCM: 3.20 g/dL, SFO: 2.60 g/dL, oral iron: 1.70 g/dL). The median serum ferritin level at 8 weeks after FCM treatment was 43.70 ng/mL for ≤500 mg, versus 123.30 ng/mL for >500 to ≤1500 mg. All groups had a low proportion of serum ferritin and transferrin saturation (TSAT) testing at diagnosis (<38%), which decreased further for post-treatment assessment (<24%). This study suggests the importance of prescribing an appropriate total iron cumulative dose per the package insert, along with diagnosis and assessments based on serum ferritin/TSAT.

Factors affecting responsiveness of vadadustat in patients with anemia associated with chronic kidney disease: a post-hoc subgroup analysis of Japanese phase 3 randomized studies

BACKGROUND

Vadadustat is an oral hypoxia-inducible factor prolyl hydroxylase inhibitor developed for treating anemia in chronic kidney disease (CKD). The purpose of this post-hoc analysis was to investigate the factors affecting the responsiveness to vadadustat in anemia patients with nondialysis-dependent (NDD) or hemodialysis-dependent (HDD) CKD in two Japanese phase 3 studies.

METHODS

Of 151 and 162 patients enrolled in NDD-CKD and HDD-CKD studies, 136 and 140 patients, respectively, were included and divided into subgroups for the analysis. To assess vadadustat responsiveness, the resistance index was defined as the mean body weight-adjusted dose of vadadustat (mg/kg) at weeks 20-24 divided by the mean hemoglobin (g/dL) at weeks 20-24. Multivariate analysis was performed to identify the variables affecting the resistance index.

RESULTS

Independent factors identified as determinants for better response to vadadustat were as follows: high baseline hemoglobin, low baseline eGFR, high week-20-24 ferritin, and CKD not caused by autoimmune disease/glomerulonephritis/vasculitis in NDD-CKD; and male sex, high baseline C-reactive protein, and low baseline erythropoiesis-stimulating agent resistance index (ERI) in HDD-CKD.

CONCLUSIONS

In this post-hoc analysis, several factors were identified as affecting the response to vadadustat. These results may provide useful information leading to an appropriate dose modification for vadadustat.

CLINICAL TRIAL REGISTRATION

NCT03329196 (MT-6548-J01) and NCT03439137 (MT-6548-J03).

Development of a prognostic risk score to predict early mortality in incident elderly Japanese hemodialysis patients

BACKGROUND

Information of short-term prognosis after hemodialysis (HD) introduction is important for elderly patients with chronic kidney disease (CKD) and their families choosing a modality of renal replacement therapy. Therefore, we developed a risk score to predict early mortality in incident elderly Japanese hemodialysis patients.

MATERIALS AND METHODS

We analyzed data of incident elderly HD patients from a nationwide cohort study of the Japanese Society for Dialysis Therapy Renal Data Registry (JRDR) to develop a prognostic risk score. Candidate risk factors for early death within 1 year was evaluated using multivariate logistic regression analysis. The risk score was developed by summing up points derived from parameter estimate values of independent risk factors. The association between risk score and early death was tested using Cox proportional hazards models. This risk score was validated twice by using an internal validation cohort derived from the JRDR and an external validation cohort collected for this study.

RESULTS

Using the development cohort (n = 2,000), nine risk factors were retained in the risk score: older age (>85), yes = 2, no = 0; sex, male = 2, female = 0; lower body mass index (<20), yes = 2, no = 0; cancer, yes = 1, no = 0; dementia, yes = 3, no = 0; lower creatinine (<6.5 mg/dL), yes = 1, no = 0; lower albumin (<3.0 g/dL), yes = 3, no = 0; normal or high calcium (≥8.5 mg/dL), yes = 1, no = 0; and higher C reactive protein (>2.0 mg/dL), yes = 2, no = 0. In the internal and external validation cohorts (n = 739, 140, respectively), the medium- and high-risk groups (total score, 6 to 10 and 11 or more, respectively) showed significantly higher risk of early death than the low-risk group (total score, 0 to 5) (p<0.001).

CONCLUSION

We developed a prognostic risk score predicting early death within 1 year in incident elderly Japanese HD patients, which may help detect elderly patients with a high-risk of early death after HD introduction.

Risk Factors for Thromboembolic Events in Patients With Dialysis-Dependent CKD: Pooled Analysis of Phase 3 Roxadustat Trials in Japan

INTRODUCTION

Thromboembolic events have occurred in clinical trials of roxadustat. This post hoc analysis explored potential factors related to thromboembolic events in dialysis-dependent patients treated with roxadustat in four phase 3 clinical trials in Japan.

METHODS

Thromboembolic events with onset before and after week 12 were evaluated. Baseline risk factors for thromboembolic events were investigated by Cox regression analyses. Nested case-control analyses using conditional logistic models with matched pairs of case-control data explored relationships between thromboembolic events and laboratory parameters.

RESULTS

Of the 444 patients, 56 thromboembolic events were observed in 44 patients during ≤ 52 weeks of treatment. The proportion of venous and arterial thromboembolic events gradually increased after week 12. Baseline risk factors included hemodialysis (vs peritoneal dialysis), advanced age (≥ 65 years), shorter dialysis vintage (< 4 months), and history of thromboembolism. The absence of concomitant intravenous or oral iron therapy (including ferric citrate) was associated with thromboembolic events before week 12 (hazard ratio 11.25; 95% confidence interval [CI] 3.36-37.71; vs presence). Case-control analysis revealed that low average transferrin saturation (< 10%; unadjusted odds ratio [OR] 6.25; 95% CI 1.52-25.62; vs ≥ 20%), high average transferrin level (≥ 2.5 g/L; unadjusted OR 4.36; 95% CI 1.23-15.39; vs < 2.0 g/L), and high average roxadustat dose (≥ 150 mg; unadjusted OR 5.95; 95% CI 1.07-33.16; vs < 50 mg) over the previous 8 weeks before the event onset were associated with thromboembolic events after week 12. However, adjustment for iron status extinguished the significant relationship between roxadustat dose and events. Multivariate case-control analysis showed that increased transferrin from baseline (≥ 1.0 g/L; adjusted OR 7.85; 95% CI 1.82-33.90; vs < 0.5 g/dL) and decreased mean corpuscular volume (< - 2 fL; adjusted OR 5.55; 95% CI 1.73-17.83; vs ≥ 0 fL) were associated with increased risk of thromboembolic events.

CONCLUSION

In addition to established risk factors, iron deficiency may be related to thromboembolic events. Graphical Abstract available for this article.

TRIAL REGISTRATION

NCT02780726, NCT02952092, NCT02780141, NCT02779764.

Zinc Supplementation Enhances the Hematopoietic Activity of Erythropoiesis-Stimulating Agents but Not Hypoxia-Inducible Factor-Prolyl Hydroxylase Inhibitors

Since zinc is involved in many aspects of the hematopoietic process, zinc supplementation can reduce erythropoiesis-stimulating agents (ESAs) in patients undergoing hemodialysis. However, it remains unclear whether hypoxia-inducible factor-prolyl hydroxylase inhibitors (HIF-PHIs) have similar reduction effects. HIF-PHI stabilizes HIF, which promotes hematopoiesis, although HIF-1α levels are downregulated by zinc. This study aimed to investigate the effect of zinc supplementation on the hematopoietic effect of HIF-PHI in patients undergoing hemodialysis. Thirty patients undergoing maintenance hemodialysis who underwent periods of treatment with roxadustat or darbepoetin alfa during the past 3 years were retrospectively observed. Participants who underwent periods with and without zinc supplementation were selected, with nine treated with darbepoetin alfa and nine treated with roxadustat. Similarly to the ESA responsiveness index (ERI), the hematopoietic effect of zinc supplementation was determined by the HIF-PHI responsiveness index (HRI), which was calculated by dividing the HIF-PHI dose (mg/week) by the patient's dry weight (kg) and hemoglobin level (g/L). Zinc supplementation significantly increased ERI (p < 0.05), but no significant change was observed (p = 0.931) in HRI. Although zinc supplementation did not significantly affect HRI, adequate zinc supplementation is required to alleviate concerns such as vascular calcification and increased serum copper during the use of HIF-PHI.

Efficacy of Hypoxia-Inducible Factor Prolyl Hydroxylase Inhibitor on Clinical Parameters in Patients with Heart Failure

Background and Objectives: Hypoxia-inducible factor prolyl hydroxylase (HIF-PH) inhibitors have been approved as an oral drug for treating anemia in chronic kidney disease (CKD). However, the clinical effect of HIF-PH inhibitors in patients with heart failure (HF) is unclear. Thus, this study investigated the effect of HIF-PH inhibitors in patients with HF and CKD. Materials and Methods: Thirteen patients with HF complicated by renal anemia who were started on vadadustat were enrolled. Clinical parameters were compared before and 1 month after vadadustat was started. Results: The mean left ventricular ejection fraction was 49.8 ± 13.9%, and the mean estimated glomerular filtration rate was 29.4 ± 10.6 mL/min/1.73 m2. The hemoglobin level was significantly increased (9.7 ± 1.3 mg/dL vs. 11.3 ± 1.3 mg/dL, p < 0.001), and the N-terminal prohormone of B-type natriuretic peptide was significantly decreased after the introduction of vadadustat [4357 (2651-15182) pg/mL vs. 2367 (1719-9347) pg/mL, p = 0.002]. Furthermore, the number of patients with New York Heart Association functional class ≥ 3 was also decreased after the introduction of vadadustat [8 (61.5%) vs. 1 (7.7%), p = 0.008]. No thromboembolic adverse events or new tumors were observed in any patient during the study period. Conclusions: The introduction of vadadustat in patients with HF complicated by renal anemia led to improvements in anemia and symptoms of HF.

Role of Erythropoiesis-Stimulating Agents in Cardiovascular Protection in CKD Patients: Reappraisal of Their Impact and Mechanisms

Erythropoiesis-stimulating agents (ESAs) have markedly reduced the need for blood transfusion for renal anemia and are included in standard therapies for patients with chronic kidney disease (CKD). Various protective effects of ESAs on the cardiovascular system have been discovered through basic research, and the effects have received much attention because the rates of cardiovascular events and mortality are high in CKD patients. However, randomized clinical trials did not provide strong evidence that ESAs exert cardioprotection in humans, including CKD patients. It is difficult to assess the cardioprotective effects of ESAs in CKD patients through the clinical data that has been reported to date because the relationship between hemoglobin level rather than ESA dose and cardiovascular event rates was examined in most studies. Interestingly, recent studies using a rat model of CKD showed that the infarct size-limiting effect of an ESA was lost when its dose was increased to a level that normalized blood hemoglobin levels, suggesting that the optimal dose of an ESA for myocardial protection is less than the dose required to normalize hemoglobin levels. Furthermore, animal models of traditional coronary risk factors or comorbidities were resistant to the cardioprotective effects of ESAs because of interruptions in signal-mediated mechanisms downstream of erythropoietin receptors. In this review, we briefly discuss basic and clinical data on the impact of anemia on coronary and systemic circulation, the effects of CKD on the cardiovascular system, and the multiple pharmacological actions of ESAs to examine whether the ESAs that are prescribed for renal anemia exert any cardioprotection in patients with CKD.

Association between serum iron markers, iron supplementation and cardiovascular morbidity in pre-dialysis chronic kidney disease

BACKGROUND

The optimal range of serum iron markers and usefulness of iron supplementation are uncertain in patients with pre-dialysis chronic kidney disease (CKD). We investigated the association between serum iron indices and risk of cardiovascular disease (CVD) events and the effectiveness of iron supplementation using Chronic Kidney Disease Japan Cohort data.

METHODS

We included 1416 patients ages 20-75 years with pre-dialysis CKD. The tested exposures were serum transferrin saturation and serum ferritin levels and the outcome measures were any cardiovascular event. Fine-Gray subdistribution hazard models were used to examine the association between serum iron indices and time to events. The multivariable fractional polynomial interaction approach was used to evaluate whether serum iron indices were effect modifiers of the association between iron supplementation and cardiovascular events.

RESULTS

The overall incidence rate of CVD events for a median of 4.12 years was 26.7 events/1000 person-years. Patients with serum transferrin saturation <20% demonstrated an increased risk of CVD [subdistribution hazard ratio (HR) 2.13] and congestive heart failure (subdistribution HR 2.42). The magnitude of reduction in CVD risk with iron supplementation was greater in patients with lower transferrin saturations (P = .042).

CONCLUSIONS

Maintaining transferrin saturation >20% and adequate iron supplementation may effectively reduce the risk of CVD events in patients with pre-dialysis CKD.

Co-Administration of Roxadustat and Zinc Stabilizes Both Serum Copper and Zinc Concentrations in Patients Undergoing Hemodialysis

Patients undergoing hemodialysis often require zinc supplementation owing to hypozincemia, which may reduce serum copper concentrations. However, hypoxia-inducible factor-prolyl hydroxylase inhibitors (HIF-PHIs), which are used to treat renal anemia, have been reported to increase serum copper. Therefore, this study investigates the effectiveness of a combination of HIF-PHIs and zinc for the stabilization of serum copper and zinc concentrations during zinc supplementation for patients undergoing hemodialysis with renal anemia and hypozincemia. The serum zinc and copper concentrations were retrospectively compared over an 8-month period in 20 patients being administered roxadustat (an HIF-PHI) and 20 controls. The changes in concentrations were tracked in participants taking roxadustat who initiated or increased zinc supplementation. The serum zinc concentrations of the participants were significantly higher (p < 0.001) during zinc supplementation, regardless of roxadustat administration. Post-roxadustat, the serum copper concentrations were significantly higher than those pre-roxadustat or in non-roxadustat-treated participants, irrespective of zinc supplementation (p < 0.005). Even post-roxadustat, the serum copper concentrations were significantly lower, with no increase during zinc supplementation (p < 0.040). When zinc supplementation was initiated or increased in participants taking roxadustat, copper and zinc concentrations were normalized. Thus, combining zinc supplementation with roxadustat prevents both an excessive increase in serum copper and a decrease in serum zinc.

Association of Estimated Total Body Iron with All-Cause Mortality in Japanese Hemodialysis Patients: The Miyazaki Dialysis Cohort Study

Iron deficiency/excess may be associated with worse prognosis in patients undergoing hemodialysis. This study ascertained the association of the estimated total body iron (TBI) with mortality in patients receiving hemodialysis. Multicenter clinical data collected in the Miyazaki Dialysis Cohort Study from 943 patients receiving hemodialysis were analyzed after stratification into tertile categories by baseline TBI-estimated as the heme iron plus iron storage from ferritin levels. The primary outcome was a 5-year all-cause mortality; hazard ratios of the TBI-all-cause mortality association were estimated using Cox models adjusted for potential confounders, including clinical characteristics, laboratory, and drug data, wherein patients with high TBI were the reference category. The receiver operating characteristic (ROC) curve analyses of TBI, serum ferritin levels, and transferrin saturation were performed to predict all-cause mortality; a total of 232 patients died during the follow-up. The low TBI group (<1.6 g) had significantly higher hazard ratios of mortality than the high TBI group (≥2.0 g). As ROC curve analyses showed, TBI predicted mortality more accurately than either levels of serum ferritin or transferrin saturation. Lower TBI increases the mortality risk of Japanese hemodialysis patients, and further studies should examine whether iron supplementation therapy that avoids low TBI improves prognosis.

Association between iron status markers and kidney outcome in patients with chronic kidney disease

Several studies conducted in patients with various stages of chronic kidney disease (CKD) have investigated the association of iron status markers, such as transferrin saturation (TSAT) and serum ferritin, with kidney outcomes. However, the associations were inconsistent and remain strongly debated. Therefore, we aimed to investigate whether TSAT and serum ferritin levels were associated with kidney outcome in such a population. In this study, 890 patients who were admitted for the evaluation of and education for CKD were prospectively followed. Primary kidney outcome was a composite of doubling of serum creatinine, end-stage kidney disease, or death due to kidney failure. Participants were divided into quartiles (Q1-Q4) according to TSAT or serum ferritin levels. During a median follow-up period of 2.8 years, kidney events occurred in 358 patients. In the multivariable Cox analyses, compared with Q3 of TSAT, the hazard ratios (95% confidence intervals) for Q1, Q2, and Q4 were 1.20 (0.87, 1.66), 1.38 (1.01, 1.87), and 1.14 (0.82, 1.59), respectively. Compared with Q2 of serum ferritin, lower and higher quartiles had a significantly increased risk for kidney outcome; hazard ratios (95% confidence intervals) for Q1, Q3, and Q4 were 1.64 (1.18, 2.27), 1.71 (1.24, 2.37), and 1.52 (1.10, 2.10), respectively. A Fine-Gray model with death before kidney events as a competing risk showed results similar to the above. In CKD, lower and higher ferritin levels were independent risk factors for kidney disease progression.

Anemia combined with albuminuria increases the risk of cardiovascular and renal events, regardless of a reduced glomerular filtration rate, in patients with type 2 diabetes: a prospective observational study

Aim

The incidence of cardiovascular and renal events was investigated in patients with type 2 diabetes who were classified according to anemia and the components of dialysis-independent chronic kidney disease (CKD) in a prospective observational study.

Methods

A population of 778 Japanese patients with type 2 diabetes was prospectively analyzed for 4 years. The outcomes were the incidence of cardiovascular events and renal events.

Results

In all subjects, the incidence of cardiovascular and renal events was found to be 5% and 11%, respectively. Even after adjusting for a reduced estimated glomerular filtration rate (eGFR <60 mL/min/1.73 m2), the incidence of cardiovascular events was significantly higher (hazard ratio [HR]: 5.73) in patients with anemia and albuminuria than in those without anemia and albuminuria. The incidence of renal events was significantly higher in patients with no anemia and albuminuria (HR: 2.93) and further in those with anemia and albuminuria (HR: 7.56) than in those without anemia and albuminuria even after adjusting for a reduced eGFR.

Conclusion

Anemia combined with albuminuria is a risk factor for vascular events in patients with type 2 diabetes, regardless of the eGFR.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13340-023-00637-x.

Effects of iron-based phosphate binders on mortality and cardiovascular events in patients receiving maintenance dialysis

Phosphate binders are the main treatment for hyperphosphatemia in patients with chronic kidney disease, and iron-based phosphate binders have been used with increasing frequency in recent years. This study examined the association of the use of iron-based, rather than non-iron-based, phosphate binders with the incidence of cardiovascular events, in a real-world setting. We used data from a cohort comprising representative adult patients on maintenance hemodialysis in Japan. The exposure of interest was the time-varying use of phosphate binders, classified into "iron-based", "only non-iron-based", and "no use". The primary outcome was a composite of cardiovascular events and all-cause deaths. A marginal structural Cox regression model was used to deal with possible time-dependent confounding. Of the 2247 patients from 58 hemodialysis facilities, iron-based and only non-iron-based phosphate binders were used in 328 (15%) and 1360 (61%), respectively, at baseline. Hazard ratios (95% confidence intervals) for iron-based and non-iron-based phosphate binders versus no use of phosphate binders were 0.35 (0.24, 0.52) and 0.44 (0.33, 0.58), respectively. The hazard ratio for iron-based relative to non-iron-based phosphate binders was 0.81 (0.58, 1.13), which was not statistically significant. Further studies are warranted to elucidate whether the use of iron-based phosphate binders reduces the event rate.

Anemia Treatment, Hemoglobin Variability, and Clinical Events in Patients With Nondialysis-Dependent CKD in Japan

Key Points

This large, contemporary study reports the management of anemia in a real-world cohort of patients with nondialysis-dependent CKD from multifaceted aspects. This study highlights the suboptimal and heterogeneous treatment of anemia in clinical practice. The findings also underscore the importance of maintaining a stable hemoglobin concentration within the target range to reduce the risk of mortality and morbidity.

Background

Anemia management in patients with nondialysis-dependent CKD has attracted attention with the introduction of novel therapeutic agents; however, few studies have provided comprehensive epidemiologic information.

Methods

A retrospective cohort study was conducted in adult patients with stage ≥3a nondialysis-dependent CKD and hemoglobin (Hb) <11 g/dl (January 2013–November 2021; N =26,626) to assess longitudinal treatment patterns, Hb, and iron parameters (ferritin and transferrin saturation) for anemia management. Time-dependent Cox proportional hazard models were applied to assess the risk of clinical events, including death, cardiovascular events, dialysis introduction, and red blood cell transfusion, associated with temporal fluctuation patterns of Hb levels.

Results

The cumulative incidence of anemia treatment initiation within 12 months was 37.1%, including erythropoiesis-stimulating agents 26.5%, iron oral 16.8%, iron intravenous 5.1%, and hypoxia-inducible factor prolyl hydroxylase inhibitor 0.2%. The mean (±SD) Hb levels were improved from 9.9±1.2 to 10.9±1.6 g/dl at 12 months. Despite erythropoiesis-stimulating agents or hypoxia-inducible factor prolyl hydroxylase inhibitor therapy, 30.1% of patients remained Hb <10 g/dl. The risks of premature death, cardiovascular events, dialysis introduction, and red blood cell transfusion were significantly higher in groups with consistently low Hb or low-amplitude Hb fluctuation around the lower limit of target Hb range than in patients with target Hb range (P < 0.05). Similarly, significantly higher risks for dialysis introduction and red blood cell transfusion were associated with high-amplitude Hb fluctuation across target Hb range were observed.

Conclusions

The findings underscore the importance of stable Hb control within the target range to reduce the mortality and morbidity risks in patients with nondialysis-dependent CKD while highlighting the suboptimal and heterogeneous treatment of anemia in clinical practice.

Iron Parameters in Patients Treated with Roxadustat for Anemia of Chronic Kidney Disease

Roxadustat is a novel agent with a distinct mechanism of action compared to erythropoiesis-stimulating agents (ESAs) and a potentially different combination of effects on iron parameters. This narrative review describes the effects of roxadustat on iron parameters and on hemoglobin levels in the context of iron supplementation in patients with anemia of non-dialysis-dependent (NDD) or dialysis-dependent (DD) chronic kidney disease (CKD). Roxadustat use was associated with a greater reduction in serum ferritin levels than seen with ESAs and an increase in serum iron levels compared to a decrease with ESAs. Decreases in transferrin saturation in patients treated with roxadustat were relatively small and, in the case of patients with NDD CKD, not observed by Week 52. These changes reflect the concomitant increases in both serum iron and total iron-binding capacity. Compared to placebo and an ESA, roxadustat improved iron availability and increased erythropoiesis while requiring less intravenous iron use. Hepcidin levels generally decreased in patients who received roxadustat compared to baseline values in all CKD populations; these decreases appear to be more robust with roxadustat than with an ESA or placebo. The mechanisms behind the effects of roxadustat and ESAs on iron availability and stores and erythropoiesis appear to differ and should be considered holistically when treating anemia of CKD.

Relationship Between the Effect of Roxadustat and Comorbid Diabetes in Non-dialyzed Chronic Kidney Disease Patients: A Retrospective Observational Study

Introduction The dose of roxadustat, a hypoxia-inducible factor prolyl hydroxylase (HIF-PH) inhibitor, required to treat anemia, the hemoglobin level and the rate of hemoglobin target achievement were retrospectively investigated in non-dialyzed chronic kidney disease (CKD) patients with and without type 2 diabetes. Methods As the full analysis set, 25 subjects (10 with diabetes and 15 without diabetes) were observed over six months among 44 non-dialyzed CKD patients who received roxadustat. The target hemoglobin level was set at 110-130 g/L. Results The comorbidities of diabetes and body weight at baseline were significantly associated with each dose of roxadustat at six months and the change in each dose of roxadustat from the initiation of roxadustat treatment. There was no significant difference in the amount of increase in the hemoglobin level (14±11 g/L vs. 15±8 g/L) and the rate of hemoglobin target achievement (70% vs. 67%) between patients with and without diabetes. Each dose of roxadustat gradually decreased in patients without diabetes, whereas it increased in those with diabetes. Each dose of roxadustat was significantly higher in patients with diabetes than in those without diabetes at 3 (60±21 mg vs. 42±14 mg) and 6 (61±22 mg vs. 41±14 mg) months after the initiation of roxadustat treatment. Conclusion Roxadustat is useful for the treatment of anemia in both CKD patients with and without diabetes. However, the dose required to achieve the target hemoglobin level may be higher in patients with diabetes than in those without diabetes.

Not baseline but time-dependent erythropoiesis-stimulating agent responsiveness predicts cardiovascular disease in hemodialysis patients receiving epoetin beta pegol: A multicenter prospective PARAMOUNT-HD Study

BACKGROUND

Responsiveness to erythropoiesis-stimulating agents (ESAs) has been reported to be associated with increased cardiovascular disease (CVD) and mortality in patients undergoing hemodialysis (HD). However, the association between hyporesponsiveness to the long-acting ESA, epoetin beta pegol (CERA), and CVD remains unknown.

METHODS

This multicenter prospective study included 4034 patients undergoing maintenance HD. After shifting from prior ESA to CERA, we studied the association between erythropoietin resistance index (ERI) at six months and outcomes, including cardiac events, major adverse cardiovascular events (MACE), and all-cause mortality, using Cox proportional hazards models (Landmark analyses) and marginal structural models to adjust for time-dependent confounding factors, including iron-containing medications and hemodiafiltration (HDF).

RESULTS

The median dialysis vintage and the observational period were 5.0 years and 22.1 months, respectively. The landmark analyses revealed that the highest tertile of baseline ERI (T3) was associated with a significantly higher all-cause mortality than the lowest tertile (T1) (hazard ratio [HR]: 1.48, 95% CI: 1.03-2.13). Furthermore, marginal structural models revealed that time-dependent ERI T3 was significantly associated with increased cardiac events (HR: 1.59, 95% CI: 1.14-2.23), MACE (HR: 1.60, 95% CI: 1.19-2.15), all-cause mortality (HR: 1.97, 95% CI: 1.40-2.77), and heart failure (HF) (HR: 2.05, 95% CI: 1.23-3.40) compared to T1. A linear mixed effects model showed that iron-containing medications and HDF are negatively associated with time-dependent ERI.

CONCLUSIONS

Baseline ERI at six months predicted only all-cause mortality; however, time-dependent ERI was a predictor of cardiac events, all-cause mortality, MACE, and HF. The widespread use of iron-containing medications and HDF would ameliorate ESA hyporesponsiveness.

Changes in erythropoiesis-stimulating agent responsiveness after transfer to combined therapy with peritoneal dialysis and hemodialysis for patients on peritoneal dialysis: A prospective multicenter study in Japan

INTRODUCTION

Inadequate dialysis and fluid overload are corrected after starting combined therapy with peritoneal dialysis (PD) and hemodialysis (HD). However, the effects on anemia management has not been elucidated.

METHODS

We conducted a prospective, multicenter, observational cohort study of 40 PD patients (age, 60 ± 10 years; male, 88%; median PD duration, 28 months) starting combined therapy and investigated changes in several clinical parameters, including erythropoiesis-stimulating agent (ESA) resistance index (ERI).

RESULTS

ERI decreased significantly during 6 months after switching to combined therapy (from 11.8 [IQR 8.0-20.4] units/week/kg/(g/dL) to 7.8 [IQR 3.9-18.6] units/week/kg/(g/dL), p = 0.047). Body weight, urinary volume, serum creatinine and the dialysate-to-plasma creatinine ratio (D/P Cr) decreased, whereas hemoglobin and serum albumin increased. In subgroup analysis, the changes in ERI were not affected by cause for starting combined therapy, PD holiday and D/P Cr.

CONCLUSION

Although detailed mechanism was unclear, ESA responsiveness improved after switching from PD alone to combined therapy.

Clinical Significance of Trace Element Zinc in Patients with Chronic Kidney Disease

The trace element zinc is essential for diverse physiological processes in humans. Zinc deficiency can impair growth, skin reproduction, immune function, maintenance of taste, glucose metabolism, and neurological function. Patients with chronic kidney disease (CKD) are susceptible to zinc deficiency, which is associated with erythropoiesis-stimulating agent (ESA) hypo-responsive anemia, nutritional problems, and cardiovascular diseases as well as non-specific symptoms such as dermatitis, prolonged wound healing, taste disturbance, appetite loss, or cognitive decline. Thus, zinc supplementation may be useful for the treatment of its deficiency, although it often causes copper deficiency, which is characterized by several severe disorders including cytopenia and myelopathy. In this review article, we mainly discuss the significant roles of zinc and the association between zinc deficiency and the pathogenesis of complications in patients with CKD.

Evaluation of Hemoglobin Response to Treatment With Enarodustat Using Pharmacometric Approach in Japanese Anemic Patients With Chronic Kidney Disease

Enarodustat (JTZ-951) is a hypoxia-inducible factor prolyl hydroxylase inhibitor that has been approved and marketed in Japan for patients with anemia with chronic kidney disease (CKD). The pharmacometric approach was applied to assess the relationship between plasma concentrations of enarodustat and hemoglobin (Hb) levels, and to provide information regarding the optimal use of enarodustat in clinical practice by simulations based on the pharmacokinetic and pharmacodynamic (PK/PD) model that was developed. The PK/PD data of enarodusat obtained from phase 2 and phase 3 studies in Japanese patients with CKD were well described by the models: a 1-compartment model with first-order absorption and elimination for PK, and a semimechanistic model based on transit compartment model for PD. Although several factors were identified as statistically significant covariates on the PK/PD of enarodustat, model-based simulations showed that none of them had clinically relevant impacts on the treatment effect (ie, Hb levels) of enarodustat. Hence, enarodustat treatment provides the stable Hb control with the initial dose (hemodialysis-dependent CKD: 4 mg/day, non-dialysis-dependent CKD: 2 mg/day) and maintenance dose (1-8 mg/day) to the patients with varied demographic characteristics.

How to diagnose iron deficiency in chronic disease: A review of current methods and potential marker for the outcome

Iron deficiency (ID) is the most common nutritional disorder worldwide. It is often observed in patients with chronic diseases, such as heart failure (HF), chronic kidney disease (CKD), inflammatory bowel disease (IBD) and cancer. ID is associated with poor clinical outcome, including poor performance, reduced quality of life, as well as increased hospitalization and mortality. The aim of this review is to provide an overview about the role of ID in chronic diseases (HF, CKD, IBD, cancer) regarding their current definitions and clinical relevance; diagnostic accuracy of iron parameters in chronic inflammatory conditions and its potential as prognostic markers. Due to different definitions and guideline recommendations of ID, various laboratory parameters for ID diagnostic exist and there is no general consensus about the definition of ID and its treatment. Still, a general trend can be observed across all investigated indications of this review (HF, CKD, IBD, cancer) that serum ferritin and transferrin saturation (TSAT) are the two parameters mentioned most often and emphasized in all guidelines to define ID and guide treatment. The most commonly used threshold values for the diagnosis of ID are TSAT of < 20% and serum ferritin of < 100-300 µg/L. Noteworthy, both TSAT and particularly ferritin are frequently applied, but both may vary due to inflammatory conditions. Studies showed that TSAT is less affected by inflammatory processes and may therefore be more accurate and reliable than serum ferritin, particularly in conditions with elevated inflammatory state. A low iron status and particularly a low TSAT value was associated with a poor outcome in all investigated indications, with the strongest evidence in HF patients. Routine surveillance of iron status in these groups of patients with chronic conditions is advisable to detect ID early. Depending on the inflammatory state, TSAT < 20% may be the more accurate diagnostic marker of ID than ferritin. Moreover, TSAT may also be the more reliable estimate for the prognosis, particularly in HF.

Diagnostic accuracy and clinical usefulness of erythrocyte creatine content to predict the improvement of anaemia in patients receiving maintenance haemodialysis

BACKGROUND

The improvement of anaemia over time by erythropoiesis stimulating agent (ESA) is associated with better survival in haemodialysis patients. We previously reported that erythrocyte creatine content, a marker of erythropoietic capacity, was a reliable marker to estimate the effectiveness of ESA. The aim of this study was to examine the accuracy and clinical usefulness of erythrocyte creatine content to predict the improvement of anaemia in haemodialysis patients.

METHODS

ESA dose was fixed 3 months prior to the enrollment and was maintained throughout the study period. Erythrocyte creatine content and haematologic indices were measured at baseline in 92 patients receiving maintenance haemodialysis. Haemoglobin was also measured 3 months after. Improvement of anaemia was defined as ≥ 0.8 g/dL change in haemoglobin from baseline to 3 months.

RESULTS

Erythrocyte creatine content was significantly higher in 32 patients with improvement of anaemia compared to 60 patients with no improvement of anaemia (2.47 ± 0.74 vs. 1.57 ± 0.49 μmol/gHb, P = 0.0001). When 9 variables (erythrocyte creatine content, ESA dose, reticulocyte, haptoglobin, haemoglobin at baseline, serum calcium, intact parathyroid hormone, transferrin saturation and serum ferritin) were used in the multivariate logistic regression analysis, erythrocyte creatine emerged as the most important variable associated with the improvement of anaemia (P = 0.0001). The optimal cut-off point of erythrocyte creatine content to detect the improvement of anaemia was 1.78 μmol/gHb (Area under the curve: 0.86). Sensitivity and specificity of erythrocyte creatine content to detect the improvement of anaemia were 90.6% and 83.3%.

CONCLUSION

Erythrocyte creatine content is a reliable marker to predict the improvement of anaemia 3 months ahead in patients receiving maintenance haemodialysis.

Effects of roxadustat on anemia, iron metabolism, and lipid metabolism in patients with non-dialysis chronic kidney disease

Background

We determined the effects of roxadustat on the values of anemia, iron metabolism, renal function, proteinuria, and lipid metabolism and identified the associated factors of the change in hemoglobin levels after roxadustat administration in non-dialysis chronic kidney disease (CKD) patients who were receiving an erythropoietin-stimulating agent (ESA).

Methods

We conducted retrospective analysis of the changes in hemoglobin, serum ferritin, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglyceride levels; transferrin saturation; the estimated glomerular filtration rate; and the urinary protein/creatinine ratio over 24 weeks after the change from an ESA to roxadustat in 50 patients with non-dialysis CKD and anemia (roxadustat group). Seventy-two patients with non-dialysis CKD and anemia who proceeded ESA therapy were used as the control (ESA) group.

Results

We observed no significant between-group differences in clinical parameters at baseline except for the significantly lower hemoglobin concentration and lower proportion of diabetes mellitus in the roxadustat group. The hemoglobin concentration was significantly higher in the roxadustat group after 24 weeks (11.3 ± 1.2 versus 10.3 ± 1.0 g/dL; value of p < 0.05), whereas the transferrin saturation, ferritin concentration, estimated glomerular filtration rate, and urinary protein/creatinine ratio were not different between the two groups. TC (135.9 ± 40.0 versus 165.3 ± 38.4 mg/dL; value of p < 0.05), LDL-C (69.1 ± 28.3 versus 87.2 ± 31.5 mg/dL; value of p < 0.05), HDL-C (41.4 ± 13.5 versus 47.2 ± 15.3 mg/dL; value of p < 0.05), and triglyceride concentrations (101.5 ± 52.7 versus 141.6 ± 91.4 mg/dL, value of p < 0.05) were significantly lower in the roxadustat group compared with the ESA group at 24 weeks. Multiple linear regression analysis showed that the roxadustat dose at baseline (standard coefficient [β] = 0.280, value of p = 0.043) was correlated with the change in the hemoglobin levels during the first 4 weeks of roxadustat treatment, whereas age (β = 0.319, value of p = 0.017) and the roxadustat dose at 24 weeks (β = -0.347, value of p = 0.010) were correlated with the hemoglobin concentration after 24 weeks of roxadustat administration.

Conclusion

Roxadustat can improve anemia and reduce serum cholesterol and triglyceride levels in non-dialysis CKD patients after the patients' treatment was switched from an ESA without affecting renal function or proteinuria. These results indicate that roxadustat has superior effects to ESAs regarding anemia and lipid metabolism at the dose selected for the comparison in patients with non-dialysis CKD.

Prevalence, treatment status, medical costs, quality of life, and productivity loss in Japanese adult patients with anemia: a real-world database study

AIMS

To investigate the prevalence, treatment status, and effect of anemia on medical costs, quality of life (QOL), and productivity loss in Japan.

METHODS

This cross-sectional study used a database containing claims, health check-ups, and questionnaire data. Adults with hemoglobin data at 2020 check-ups were included. QOL and productivity loss were evaluated using EuroQol 5-Dimension (EQ-5D) and Work Productivity and Activity Impairment questionnaire data available for a subset of the population. Nationwide anemia prevalence, including both diagnosed as having anemia and undiagnosed but with low hemoglobin levels, were estimated. Treatment status was described by hemoglobin levels. Differences in medical costs, QOL, and productivity loss were compared between individuals with and without anemia. Subgroup analyses were performed using the Charlson Comorbidity Index (CCI).

RESULTS

The study population included 554,798 individuals. Anemia prevalence was estimated at 15.1% with 55.3% undiagnosed. In patients with anemia, 85.3% were untreated; 79.5% of the treated patients received only oral iron drugs. In patients with anemia, monthly medical costs were ¥17,766 higher, EQ-5D score was 0.0118 lower, and productivity loss was 2.6% higher than in those without anemia. The trends were consistent even in limited patients with CCI = 0. Nationwide annual excess medical costs, deficit QOL, and productivity loss in patients with anemia were estimated at ¥3.32 trillion, 138,000 quality-adjusted life-years, and ¥1.13 trillion, respectively.

LIMITATIONS

As the study population only included individuals who underwent health check-ups, they may be healthier than general population. Whether the differences in medical costs, QoL, and productivity loss are caused by anemia or other underlying differences in patient characteristics is unclear, given the likelihood of residual confounding.

CONCLUSIONS

The results suggest that more than half of patients with anemia were undiagnosed and untreated. Patients with anemia had higher medical costs, lower QOL, and greater productivity loss than those without anemia.

Synergistic deterioration of prognosis associated with decreased grip strength and hyporesponse to erythropoiesis-stimulating agents in patients undergoing hemodialysis

Introduction

We examined the combined effect of erythropoietin (EPO) hyporesponsiveness and low handgrip strength (HGS) on the prognosis of patients undergoing hemodialysis (HD).

Methods

We recruited patients with chronic kidney disease (CKD) Stage 5, who were undergoing HD at our dialysis clinic between January 2015 and March 2015 (n = 182). Patients of ≥20 years of age and who had been undergoing HD for ≧3 months at enrollment were eligible for inclusion. Seven patients treated with epoetin-β pegol were excluded. First, the erythropoietin resistance index (ERI) and HGS were measured. The patients were stratified by the ERI of 9.44 (U/kg/week/g/dL), and by the HGS of 28 kg for men and 18 kg for women. We then observed death and cardiovascular disease (CVD), composite endpoint (deaths or CVD) for a median of 2 years.

Results

A total of 175 patients (male, n = 122; female, n = 53; age, 34–92 years) were included in the analysis. During the observation period of 24 months, 57 events (14 deaths and 43 CVD) were observed. High ERI and low HGS were associated with a high incidence of endpoints compared to low ERI and high HGS. Among the four groups classified by ERI and HGS values, the highest risk group was the high ERI/low HGS group (HR: 4.20 95% CI 2.12–8.33).

Conclusions

EPO hyporesponsiveness combined with low HGS were found to be significant predictors of a poor outcome, and the synergistic effects of the two factors had stronger predictive ability than either single factor.

Cardiovascular events by different target hemoglobin levels in ESA-hyporesponsive hemodialysis patients: a multicenter, open-label, randomized controlled study

Background

The incidence of cardiovascular (CV) events is high in hemodialysis (HD) patients and is associated with hyporesponsiveness to erythropoiesis-stimulating agents (ESAs). However, there are no recommended target hemoglobin ranges for ESA-hyporesponsive patients.

Methods

We randomly assigned 304 ESA-treated HD patients with ESA hyporesponsiveness to a proactive treatment group (target hemoglobin level 11 g/dL) or maintenance treatment group (target hemoglobin level 9–10 g/dL), both of which received epoetin beta pegol. The primary outcome was time to the first CV event. CV events included cardiac death, heart failure, and acute coronary syndrome requiring hospitalization. The patients were followed for 24 months.

Results

The proactive and maintenance treatment groups had mean baseline hemoglobin levels of 9.34 and 9.32 g/dL, respectively. Mean hemoglobin levels during the observation period were 10.58 and 10.26 g/dL (P < 0.001), and mean durations of hemoglobin level > 10.5 g/dL were 11.5 and 8.6 months (P < 0.001), respectively. Cox proportional hazards analysis demonstrated a significantly lower risk of CV events in the proactive group (hazard ratio [HR], 0.43; 95% confidence interval [CI], 0.19–0.96). This lower risk was driven by lower incidence of hospitalization-required congestive heart failure. A longer duration of hemoglobin level > 10.5 g/dL was associated with a lower risk of CV events (HR, 0.92/month; 95% CI, 0.87–0.98).

Conclusions

Targeting hemoglobin levels of 11 g/dL with epoetin beta pegol reduces CV risk in Japanese HD patients with ESA hyporesponsiveness.

Trial registration: University Hospital Medical Information Network (UMIN) database (UMIN000010138), registered on March 1, 2013.

Safety of daprodustat in patients with anemia of chronic kidney disease: A pooled analysis of phase 3 studies in Japan

INTRODUCTION

Daprodustat is an approved treatment for anemia of chronic kidney disease (CKD) in Japan.

METHODS

This post hoc analysis evaluated pooled safety data for daprodustat from 3 phase 3 Japanese studies in dialysis-dependent and nondialysis patients with anemia of CKD.

RESULTS

Median drug exposure duration was 365 days for both daprodustat (N = 369) and injectable erythropoiesis-stimulating agent (ESA, N = 285). The incidence per 100 patient-years of on-therapy adverse events (AEs) was 363.1 and 306.4 in the daprodustat and ESA groups, respectively. The incidence per 100 patient-years of thromboembolic and retinal events were 5.55 and 6.91 (daprodustat) and 6.28 and 7.46 (ESA), respectively. Cardiovascular and malignancy events were similar between groups, although analysis of these were limited by sample size and study duration.

CONCLUSION

The safety of daprodustat was comparable to ESA in this pooled analysis, although further large-scale research is needed to evaluate long-term risks including cardiovascular and malignancy events.

Characteristics of Japanese patients with non-dialysis-dependent chronic kidney disease initiating treatment for anemia: a retrospective real-world database study

OBJECTIVE

Anemia is a common complication of chronic kidney disease (CKD). The aim of this study was to evaluate hemoglobin levels at the initiation of erythropoiesis stimulating agent (ESA) therapy in patients with non-dialysis-dependent CKD (NDD-CKD) and anemia using a large-scale administrative database in Japan.

METHODS

The longitudinal data of adult patients who initiated ESA therapy between April 2008 and December 2018 were extracted from a hospital-based administrative database. The primary outcome was hemoglobin level at the initiation of ESA therapy, whereas the exploratory outcome was hemoglobin level recorded 6 months after the onset of the ESA therapy.

RESULTS

A total of 4939 patients were included in the primary analysis. The mean hemoglobin level at the initiation of ESA therapy was 9.1 g/dL, which was lower than the level (11 g/dL) recommended for the initiation of treatment by the current Japanese treatment guidelines. Moreover, 42.1% and 15.0% of the patients had hemoglobin levels <9.0 and <8.0 g/dL, respectively, at the initiation of ESA therapy. In 2964 patients for whom hemoglobin levels at 6 months after the initiation of ESA therapy were available, the mean hemoglobin level increased to 10.3 g/dL, and 61.9% and 31.1% of these patients had hemoglobin levels ≥10.0 and ≥11.0 g/dL, respectively.

CONCLUSION

This real-world database study revealed that hemoglobin levels at the initiation of ESA therapy in new users of ESA were lower than those recommended by treatment guidelines in Japan.

Hyporesponsiveness to erythropoiesis-stimulating agent in non-dialysis-dependent CKD patients: The BRIGHTEN study

Among non-dialysis-dependent chronic kidney disease (ND-CKD) patients, a low hematopoietic response to erythropoiesis-stimulating agents (ESAs) is a predictor for poor renal and cardiovascular outcome. To assess the method for evaluating hyporesponsiveness to ESA in patients with ND-CKD, a multicenter, prospective, observational study of 1,980 adult patients with ND-CKD with renal anemia was conducted. Darbepoetin alfa (DA) and iron supplement administrations were provided according to the recommendation of the attached document and the guidelines of JSDT (Japanese Society of Dialysis and Transplantation). The primary outcomes were progression of renal dysfunction and major adverse cardiovascular events. ESA responsiveness was assessed using pre-defined candidate formulae. During the mean follow-up period of 96 weeks, renal and cardiovascular disease (CVD) events occurred in 683 (39.6%) and 174 (10.1%) of 1,724 patients, respectively. Among pre-set candidate formulae, the one expressed by dividing the dose of DA by Hb level at the 12-week DA treatment was statistically significant in predicting renal (hazard ratio [HR], 1.449; 95% confidence interval [CI], 1.231-1.705; P<0.0001) and CVD events (HR, 1.719; 95% CI, 1.239-2.386; P = 0.0010). The optimum cut-off values for both events were close to 5.2. In conclusion, hyporesponsiveness to ESA in ND-CKD cases, which is associated with a risk for renal and CVD events, may be evaluated practicably as the dose of DA divided by the Hb level at the 12-week DA treatment, and the cut-off value of this index is 5.2. A search for the causes of poor response and measures for them should be recommended in such patients. Trial registration: ClinicalTrials. gov Identifier: NCT02136563; UMIN Clinical Trial Registry Identifier: UMIN000013464.

Effects of Zinc Acetate Hydrate Supplementation on Renal Anemia with Hypozincemia in Hemodialysis Patients

INTRODUCTION AND AIMS

This study examined whether zinc supplementation with zinc acetate hydrate improved renal anemia with hypozincemia in patients undergoing hemodialysis.

METHODS

The study participants included 21 patients undergoing hemodialysis who presented with a serum zinc level < 60 mg/dL and who were administered zinc acetate hydrate at 50 mg (reduced to 25 mg, as appropriate) for 6 months. Patients with a hemorrhagic lesion, acute-phase disease (pneumonia or cardiac failure), or hematologic disease and those whose treatment was switched from peritoneal dialysis to hemodialysis were excluded. The changes in the erythropoietin resistance index (ERI) before and after zinc acetate hydrate administration were examined. ERI was defined as the dose (IU) of erythropoiesis-stimulating agent (ESA)/week/body weight (kg)/hemoglobin content (g/dL). The differences between the two groups were analyzed using the Wilcoxon signed rank sum test, and p < 0.05 was considered statistically significant.

RESULTS

The study participants included 19 men and 2 women aged 41-95 years (mean ± standard deviation (SD): 67.1 ± 13.6). The changes in the values of parameters measured before and after zinc acetate hydrate administration were as follows: Blood Hb did not change significantly, from 10.0-13.6 g/dL (11.5 ± 1.0 g/dL) to 10.2-12.4 g/dL (11.4 ± 0.7 g/dL); serum zinc concentration significantly increased, from 33.0-59.0 mg/dL μg/dL (52.4 ± 7.6 mg/dL μg/dL) to 57.0-124.0 mg/dL μg/dL (84.1 ± 16.3 mg/dL μg/dL; p < 0.01); the ESA dose significantly decreased, from 0-12,000 IU/week (5630 ± 3351 IU/week) to 0-9000 IU/week (4428 ± 2779; p = 0.04); and ERI significantly decreased, from 0.0-18.2 (8.1 ± 5.1) to 0.0-16.0 (6.3 ± 4.3; p = 0.04).

CONCLUSIONS

Zinc supplementation increased the serum zinc concentration and significantly reduced the ESA dose and ERI, suggesting that a correction of hypozincemia contributes to lessening renal anemia in these patients.

Impact of adherence to CKD-MBD guidelines on mortality among Japanese dialysis patients: an ecological study

INTRODUCTION

This study evaluated the association between prefecture-level achievement of chronic kidney disease-mineral and bone disorder (CKD-MBD) parameter targets and mortality in Japanese dialysis patients.

MATERIALS AND METHODS

We conducted an ecological study of all prefectures in Japan using data from the Japanese Society of Dialysis Therapy and National Vital Statistics between 2016 and 2017. We calculated adherence rates to recommend target ranges for CKD-MBD parameters, including phosphate, corrected calcium, and parathyroid hormone (PTH), and explored associations of these rates with prefecture-specific standardized mortality rates (SMRs) among the general population and among prevalent dialysis patients using bivariate association analysis and structural equation modeling.

RESULTS

Prefecture-level adherence to the target phosphate range was significantly and negatively associated with prefecture-specific SMRs in men (standardized estimate (β) = - 0.61, p < 0.001) and women (β = - 0.41, p < 0.001). However, prefecture-level adherence to the target corrected calcium range was significantly and negatively associated with prefecture-specific SMRs only in men (β = - 0.28, p = 0.01). Meanwhile, prefecture-level adherence to the target PTH range was significantly and positively associated with prefecture-specific SMRs in men (β = 0.23, p = 0.04). Prefecture-level SMRs of females in the general population had a significant impact on prefecture-level SMRs of female dialysis patients (β = 0.27, p = 0.03). The models explained 52% of variance in SMR for men and 33% for women.

CONCLUSION

A higher prefecture-level achievement rate of the target phosphate range recommended by the Japanese CKD-MBD guidelines was associated with a lower prefecture-specific SMR in the Japanese dialysis population.

Clinical Factors Associated with Serum Magnesium Concentration in Patients Undergoing Peritoneal Dialysis: A Single-Center Observational Study

Purpose

Magnesium (Mg) is an essential element that is associated with various physiological functions, such as maintenance of blood pressure, muscle contraction, and nerve function. In patients undergoing hemodialysis, hypomagnesemia is associated with cardiovascular and all-cause mortality. However, in patients undergoing peritoneal dialysis (PD), clinical factors associated with Mg have not been fully investigated.

Patients and Methods

Clinical factors including anthropometric data, comorbidities, laboratory data, medications, and dialysis methods were collected from the medical records of patients undergoing PD. The associations of these factors with the serum Mg concentration were investigated by univariate and multivariate analyses.

Results

Sixty patients undergoing PD were investigated. The univariate analysis showed that the serum Mg concentration was significantly associated with treatment by hybrid PD (daily PD + once-weekly hemodialysis) (β = 0.264, P = 0.04), administration of phosphate binders (β = 0.294, P = 0.02), the serum C-reactive protein concentration (β = -0.318, P = 0.01), the serum potassium (K) concentration (β = 0.451, P < 0.01), and the serum intact parathormone concentration (β = -0.333, P = 0.01). The multivariate analysis using these factors showed an independent association between the serum Mg and K concentrations (β = 0.333, P = 0.01).

Conclusion

The serum Mg concentration was independently associated with the serum K concentration in patients undergoing PD.

Prevalence, treatment status, and predictors of anemia and erythropoietin hyporesponsiveness in Japanese patients with non-dialysis-dependent chronic kidney disease: a cross-sectional study

BACKGROUND

Hyporesponsiveness to erythropoiesis-stimulating agents (ESAs) has been highlighted as a potential risk factor for cardiovascular disease in patients with chronic kidney disease (CKD).

METHODS

We assessed cross-sectionally the prevalence, associated factors, and treatment status of anemia and ESA hyporesponsiveness in 4460 non-dialysis-dependent CKD patients enrolled in a multicenter cohort in Japan. Anemia was defined as a hemoglobin (Hb) level of less than 11 g/dL or receiving ESA therapy. ESA hyporesponsiveness was defined by the erythropoietin-resistance index (ERI), which was the erythropoietin dose per week divided by body weight and Hb level (U/kg/week/g/dl).

RESULTS

Of the 4460 patients, 1050 (23.5%) had anemia. ESAs were administered to 626 patients, reaching a percentage of 57.5% of patients with stage G5 CKD. However, the ESA treatment rate was only 49.0% in patients with a hemoglobin level of < 11 g/dL. The proportion of patients receiving iron supplementation was lower than that of patients receiving ESAs regardless of CKD stage or hemoglobin level, and a significant proportion of patients did not receive iron supplementation, even those with iron deficiency. The ERI increased with CKD stage progression, and the multiple regression analysis showed that age, female sex, body mass index, cholesterol, glomerular filtration rate, and intact parathyroid hormone level were independent contributors.

CONCLUSIONS

Our findings demonstrate that many Japanese patients with non-dialysis-dependent CKD receiving ESAs fail to maintain adequate hemoglobin levels. These results suggest the need for interventions for ESA hyporesponsiveness factors in addition to iron supplementation.

Safety and effectiveness of ferric citrate hydrate in serum phosphorus management of patients with chronic kidney disease: a long-term, real-world, observational, post-marketing surveillance study

Background

Ferric citrate hydrate (FC) is an oral iron-based phosphate binder that is used to treat hyperphosphatemia in patients with chronic kidney disease (CKD). This post-marketing surveillance study was performed to investigate the long-term safety and effectiveness of FC.

Methods

This prospective, multicenter, observational post-marketing surveillance study was performed in a real-world setting in Japan. The study involved CKD patients with hyperphosphatemia receiving FC who were undergoing either hemodialysis or peritoneal dialysis or were non-dialysis-dependent. Adverse drug reactions, iron- and erythrocyte-related parameters (i.e., levels of serum ferritin, transferrin saturation, and hemoglobin), and serum levels of phosphorus, corrected calcium, and intact parathyroid hormone were monitored for up to 104 weeks.

Results

Safety was evaluated in 2723 patients. Of these patients, 20.5% discontinued FC because of adverse events, and 3.9% discontinued FC because of unsatisfactory effectiveness. Iron-related parameters gradually increased after the initiation of FC treatment but stabilized after week 36. Effectiveness was analyzed in 2367 patients. Serum phosphorus immediately decreased, and the effect persisted for 104 weeks.

Conclusion

In this 104 week surveillance study, no new safety concerns were noted. The safety profile was not obviously different from those in pre-approval clinical trials and the 52 week interim report of this surveillance study. The serum ferritin level of most patients was below the upper limit of the target range, and iron overload risk was not evident. Long-term FC treatment effectively controlled serum phosphorus.

Prescription rate of erythropoietin-stimulating agents is low for patients with renal impairment under non-nephrology care in a tertiary-level academic medical center in Japan

BACKGROUND

Erythropoiesis-stimulating agents (ESAs) and iron supplements may be prescribed appropriately under nephrology care. However, there are few reports detailing the differences in prescription rates of these therapies among clinical departments.

METHODS

A total of 39,585 patients with renal impairment were enrolled from a database of 914,280 patients. Patients were selected based on an estimated glomerular filtration rate (eGFR) less than 60 ml/min/1.73 m². There were eight clinical departments from internal medicine, including nephrology. We defined a hemoglobin level less than 11.0 g/dL as anemia and set 20% of transferrin saturation and 100 ng/mL of serum ferritin as cutoff points. We compared the prescription rates of ESAs and iron supplementation based on the hemoglobin level and iron status among the patients seen across the eight clinical departments.

RESULTS

The lower the eGFR, the more the number of patients seen under nephrology care. The rates of patients with no prescription were 52.3, 39.9, 45.9, and 54.3% among those with hemoglobin levels of < 8, 8 ≤  < 9, 9 ≤  < 10, and 10 ≤  < 11 g/dL, respectively. Of the patients with less than 11.0 g/dL of hemoglobin, 77.3% were prescribed ESAs under nephrology care. Meanwhile, only 18.5 and 8.2% of patients were prescribed ESAs in clinical departments of internal medicine, other than nephrology, and non-internal medicine care, respectively.

CONCLUSION

Treatment for anemia has not been sufficiently performed in patients with renal impairment under non-nephrology care in a real-world clinical setting.

Anemia and its predictors among adult non-dialysis chronic kidney disease patients in Southern Ethiopia: a cross-sectional study

BACKGROUND

Anemia is an adverse outcome and common complication in chronic kidney disease patients. This is usually associated with iron deficiency, inflammation and blood loss. However, little is known about the prevalence of anemia and its predictors among chronic kidney disease patients in Southern Ethiopia. This study aimed to determine anemia and its predictors among adult non-dialysis chronic kidney disease patients in Southern Ethiopia.

METHODS

A cross-sectional study was conducted on 384 chronic kidney disease patients from February to April 2019. Socio-demographic and clinical data were collected using questionnaires and medical records. Adjusted hemoglobin was taken to define anemia using the level of Hgb <13 mg/dL for males and <12 mg/dL for females; and blood films and serum ferritin were done for anemic participants. SPSS version 25.0 was used for data analysis. Frequency distribution tables and graphs were used to describe descriptive statistics. A bivariate logistic regression model was used to determine the predictors; p <.05 was considered statistically significant.

RESULTS

Overall prevalence of anemia was 44.0% (95% CI: 39.0%, 48.9%); of which 7.1%, 62.1% and 30.8% of anemic patients had mild, moderate and severe anemia, respectively. The prevalence of anemia increased from 20.6% in stage 2 to 100% in stage 5. Morphologically, normocytic normochromic anemia was the most predominant type. Cardiovascular disease (AOR = 2.37, 95% CI: 1.35, 4.16), diabetes mellitus (AOR = 2.77, 95% CI: 1.08, 7.14), stage 3b chronic kidney disease (AOR = 2.74, 95% CI: 1.31, 5.73) and stage 4 and 5 chronic kidney disease patients (AOR = 7.11, 95% CI: 3.22, 15.72) showed significant association with anemia.

CONCLUSION

Anemia was a severe public health problem and associated with cardiovascular disease, diabetes mellitus and stages of chronic kidney disease. Thus, early diagnosis, treatment and prevention of anemia are recommended.

Darbepoetin alfa injection versus epoetin alfa injection for treating anemia of Chinese hemodialysis patients with chronic kidney failure: A randomized, open-label, parallel-group, non-inferiority Phase III trail

Background

Erythropoietin is a glycoprotein that mainly regulates erythropoiesis. In patients with chronic renal failure with anemia, darbepoetin alfa can stimulate erythropoiesis, correct anemia, and maintain hemoglobin levels. This study was designed to demonstrate the efficacy and safety of darbepoetin alfa injections as being not inferior to epoetin alfa injections (Recombinant Human Erythropoietin injection, rHuEPO) when maintaining hemoglobin (Hb) levels within the target range (10.0-12.0 g/dL) for the treatment of renal anemia.

Methods

Ninety-five patients were enrolled in this study from April 15, 2013 to April 10, 2014 at 25 sites. In this study, patients (n = 95) aged 18-70 years were randomized into a once per week intravenous darbepoetin alfa group (n = 56) and a twice or three times per week intravenous epoetin alfa group (n = 39) for 28 weeks, who had anemia with hemoglobin levels between 6 g/dL and 10 g/dL due to chronic kidney disease (CKD) and were undergoing hemodialysis or hemofiltration with ESA-naive (erythropoiesis stimulating agent-naive). The primary efficacy profile was the mean Hb level (the non-inferiority margin was -1.0 g/dL, week 21-28); the secondary efficacy profiles were the Hb increase rate (week 0-4), the target Hb achievement cumulative rate and time, the change trends of the Hb levels, and the target Hb maintenance ratio. Adverse events (AEs) were observed and compared, and the efficacy and safety were analyzed between the two treatment groups. Additionally, the frequencies of dose adjustments between the darbepoetin alfa and epoetin alfa groups were compared during the treatment period. SAS® software version 9.2 was used to perform all statistical analyses. Descriptive statistics were used for all efficacy, safety, and demographic variable analyses, including for the primary efficacy indicators.

Results

The mean Hb level was 11.3 g/dL in the darbepoetin alfa group and 10.7 g/dL in the epoetin alfa group, respectively; the difference of the lower limits of the 95% confidence intervals (CI) between the two groups was 0.1 g/dL (>-1.0 g/dL), and non-inferiority was proven; the Hb levels started to increase in the first four weeks at a similar increase rate; no obvious differences were observed between the groups in the target Hb achievement cumulative rates, and the Hb levels as well as the target Hb level maintenance rate changed over time. The incidence of AEs was 62.5% in the darbepoetin alfa group and 76.9% in the epoetin alfa group. All the adverse events observed in the study were those commonly associated with hemodialysis.

Conclusion

Darbepoetin alfa intravenously once per week can effectively increase Hb levels and maintain the target Hb levels well, which makes it not inferior to epoetin alfa intravenously twice or three times per week. Darbepoetin alfa shows an efficacy and safety comparable to epoetin alfa for the treatment of renal anemia.

Ferric citrate hydrate is associated with a reduced cost of drugs and a smaller change in red blood cell distribution width

The ASTRIO study was a randomised, multicentre, 24-week study that compared the effects of ferric citrate hydrate (FC) and non-iron-based phosphate binders (control) on anaemia management in haemodialysis (HD) patients receiving erythropoiesis-stimulating agents (ESAs). In that study, FC reduced the doses of ESAs and intravenous iron without affecting haemoglobin (Hb); however, the cost-effectiveness of FC was unclear. We retrospectively implemented a cost-effectiveness analysis comparing the incremental cost-effectiveness ratios (ICERs) in FC (n = 42) and control (n = 40) groups in patients with serum phosphate and Hb controlled within the ranges of 3.5–6.0 mg/dL and 10–12 g/dL, respectively. Costs included drug costs of phosphate binders, ESAs, and intravenous iron. Elevated red cell distribution width (RDW) has been reported to be associated with mortality in HD patients and was therefore used as an effectiveness index. The mean (95% confidence interval) differences in drug costs and RDW between the FC and control groups were US$ − 421.36 (− 778.94 to − 63.78, p = 0.02) and − 0.83% (− 1.61 to – 0.05, p = 0.04), respectively. ICER indicated a decrease of US$ 507.66 per 1% decrease in RDW. FC was more cost-effective than non-iron-based phosphate binders. Iron absorbed via FC could promote erythropoiesis and contribute to renal anaemia treatment.

Cohort profile: Alliance for Quality Assessment in Healthcare-Dialysis (AQuAH-D) prospective cohort study of patients on haemodialysis in Japan

PURPOSE

The global burden of kidney failure is increasing, but the treatment of kidney failure varies widely between patients, between dialysis facilities and over time. The Alliance for Quality Assessment in Healthcare-Dialysis (AQuAH-D) aims to conduct efficient and timely cohort studies on associations between those variations and clinical and patient-reported outcomes.

PARTICIPANTS

Included are outpatients aged 20 years old or older who are undergoing haemodialysis and have consented to participate. A total of 2895 patients were enrolled from 25 facilities in Japan between August 2018 and July 2020 and are to be followed until 31 December 2026. Chart review and annual questionnaires are used to collect data on patient characteristics and on outcomes including quality of life. Data on medications, haemodialysis prescriptions and blood tests are obtained from existing electronic records. Data are collected retrospectively from 1 January 2017 to patient enrolment, and prospectively from patient enrolment until the end of December 2026.

FINDINGS TO DATE

To date, the mean age is 68.3 (SD 12.2) years and 35.2% are female. The most common cause of kidney failure is diabetic nephropathy (37.4%). In January 2020, the facilities' median weekly doses of erythropoietin stimulating agent (ESA) and of intravenous vitamin D ranged from 1846 to 9692 IU (epoetin alfa equivalent) and 0.78 to 2.25 µg (calcitriol equivalent), respectively. The facilities' percentages of patients to whom calcimimetics are prescribed varied from 19% to 79%. During the retrospective period (averaging 1.85 years per participant), the incidence rates of any hospitalisation and of hospitalisation due to cardiovascular disease were 67.2 and 12.0 per 100 person-years, respectively.

FUTURE PLANS

AQuAH-D data will be updated every 6 months and will be available for studies addressing a wide range of research questions, using the advantages of granular data and quality-of-life measurement of ageing patients on haemodialysis.

Evaluation of recombinant human erythropoietin responsiveness by measuring erythrocyte creatine content in haemodialysis patients

Background

One of the main causes of anaemia in patients with end-stage renal disease is relative deficiency in erythropoietin production. Eythropoiesis stimulating agent (ESA), a potent haematopoietic growth factor, is used to treat anaemia in haemodialysis patients. The effect of ESA is usually assessed by haematological indices such as red blood cell count, haemoglobin concentration and haematocrit, but erythrocyte indices do not provide information of the rapid change in erythropoietic activity. As erythrocyte creatine directly assess erythropoiesis, the aim of this study was to evaluate the effect of ESA in haemodialysis patients by measuring the erythrocyte creatine content.

Methods

ESA dose was fixed 3 months prior to the enrollment and was maintained throughout the entire study period. Erythrocyte creatine was measured with haematologic indices in 83 haemodialysis patients. Haemoglobin was also measured 3 months after.

Results

ESA dose (152.4 ± 62.9 vs. 82.2 ± 45.5 units/kg/week, P = 0.0001) and erythrocyte creatine (2.07 ± 0.73 vs. 1.60 ± 0.41 μmol/gHb, p = 0.0003) were significantly higher in 27 patients with haemoglobin <10 g/dL compared to 56 patients with haemoglobin ≥10 g/dL. There was a fair correlation between ESA dose and the concentration of creatine in the erythrocytes (r = 0.55, P < 0.0001). Increase in haemoglobin (>0.1 g/dL) was observed in 37 patients, whereas haemoglobin did not increase in 46 patients. Erythrocyte creatine levels were significantly higher in those patients with an increase in haemoglobin compared to those without (2.04 ± 0.64 vs. 1.52 ± 0.39 μmol/gHb, p < 0.0001). When 8 variables (ESA dose, erythropoietin resistance index, C-reactive protein, intact parathyroid hormone, iron supplementation, presence of anaemia, erythrocyte creatine and reticulocyte) were used in the multivariate logistic analysis, erythrocyte creatine levels emerged as the most important variable associated with increase in haemoglobin (Chi-square = 6.19, P = 0.01).

Conclusion

Erythrocyte creatine, a useful marker of erythropoietic capacity, is a reliable marker to estimate ameliorative effectiveness of ESA in haemodialysis patients.

Change in Anemia by Carnitine Supplementation in Patients Undergoing Peritoneal Dialysis: A Retrospective Observational Study

Background: Carnitine supplementation improves various dialysis-related symptoms including erythropoietin-resistant anemia in patients who are undergoing hemodialysis. However, the utility of carnitine supplementation in patients who are undergoing peritoneal dialysis (PD) is not fully understood.

Methods: Thirteen patients undergoing PD [mean age: 54.2 ± 14.8 years, males: 9/13 (69%)] administered oral carnitine supplementation (mean dose: 9.1 ± 3.3 mg/kg/day) for 4–6 months were retrospectively investigated. Changes in serum carnitine levels and other clinical variables including the erythropoietin resistance index (ERI) were analyzed after carnitine supplementation.

Results: Carnitine supplementation increased serum total carnitine (48.5 ± 10.2 vs. 130.1 ± 37.2 μmol/L, P < 0.01), free carnitine (31.1 ± 8.3 vs. 83.1 ± 24.6 μmol/L, P < 0.01), and acyl carnitine (17.4 ± 2.8 vs. 46.9 ± 13.8, P < 0.01) levels. The acyl carnitine/free carnitine ratio was not affected (0.6 ± 0.1 vs. 0.6 ± 0.1, P = 0.75). Although the mean ERI was not affected by carnitine supplementation [13.7 ± 4.7 vs. 11.6 ± 3.4 IU/kg/(g/dL)/week, P = 0.28], the ERI change rate was significantly decreased (1.00 ± 0.00 vs. 0.87 ± 0.11, P < 0.01).

Conclusion: Carnitine supplementation may improve erythropoietin resistance in patients who are undergoing PD.

Association of fibroblast growth factor 23 and α-klotho in hemodialysis patients during administration of ferric citrate hydrate: post hoc analysis of ASTRIO study

Background

Fibroblast growth factor-23 (FGF23) and α-klotho are associated with anemia in patients with chronic kidney disease. In this post hoc analysis of the ASTRIO study (UMIN000019176), we investigated the relationship between FGF23 and α-klotho during treatment with an iron-based phosphate binder, ferric citrate hydrate (FC), compared with non-iron-based phosphate binders in hemodialysis (HD) patients. We examined the effect of iron absorption by FC on the relationship between FGF23 and α-klotho. There have been few clinical studies evaluating these biomarkers simultaneously in HD patients.

Methods

The ASTRIO study was a 24-week, randomized, open-label, multicenter trial. HD patients taking non-iron-based phosphate binder(s) were randomized at a 1:1 ratio to continue other binder(s) (control group) or switch to FC (FC group). Serum phosphate (P) and hemoglobin (Hb) were maintained within 3.5–6.0 mg/dL and 10–12 g/dL, respectively. Plasma levels of intact FGF23 (i-FGF23), C-terminal FGF23 (c-FGF23), and α-klotho were measured, as were iron-related parameters. Association analyses of FGF23 and α-klotho were conducted.

Results

Patients were randomized to FC (n = 48) and control (n = 45) groups. Serum ferritin significantly increased from baseline to end-of-treatment (EOT) in the FC group, compared with the control group (adjusted mean difference [95% confidence interval]: 79.5 [44.7, 114.4] ng/mL; p <  0.001). The mean change from baseline to EOT in c-FGF23 was significantly different between the FC and control groups (mean ± standard deviation (SD): − 0.2 ± 0.8 log_e pg/mL vs. 0.2 ± 0.8 log_e pg/mL, respectively; p = 0.04). The mean change from baseline to EOT in i-FGF23 and α-klotho were not significantly different between the FC and control groups (mean ± SD: − 0.1 ± 0.8 log_e pg/mL vs. 0.1 ± 0.9 log_e pg/mL; p = 0.33, and 2.0 ± 91.5 pg/mL vs. − 8.9 ± 145.3; p = 0.58, respectively). However, both forms of FGF23 and α-klotho were not significantly associated with each other in both groups.

Conclusions

Iron absorbed via FC administration in HD patients did not influence the correlation relationship between plasma levels of FGF23 and α-klotho under the condition of serum P and Hb were maintained.

Trial registration

ASTRIO study (UMIN000019176, registered at UMIN Clinical Trials Registry on October 1, 2015).

A Phase 3 Study of Enarodustat (JTZ-951) in Japanese Hemodialysis Patients for Treatment of Anemia in Chronic Kidney Disease: SYMPHONY HD Study

INTRODUCTION

Enarodustat (JTZ-951) is a new oral hypoxia-inducible factor-prolyl hydroxylase inhibitor for the treatment of anemia in chronic kidney disease (CKD). We conducted a phase 3 study to compare the efficacy and safety of enarodustat with darbepoetin alfa (DA) in Japanese anemic patients with CKD receiving maintenance hemodialysis.

METHODS

Subjects receiving maintenance hemodialysis were randomly assigned at a 1:1 ratio to receive oral enarodustat once daily or intravenous DA every week for 24 weeks with dose adjustment every 4 weeks to maintain hemoglobin (Hb) within a target range (≥10.0 to <12.0 g/dL). The primary efficacy endpoint was difference in mean Hb level between arms during the evaluation period defined as weeks 20-24 (noninferiority margin: -1.0 g/dL). Intravenous iron preparations were prohibited during the screening period and during weeks 0-4.

RESULTS

The mean Hb level of each arm during the evaluation period was 10.73 g/dL (95% confidence interval [CI]: 10.56, 10.91) in the enarodustat arm and 10.85 g/dL (95% CI: 10.72, 10.98) in the DA arm. The difference in the mean Hb level between arms was -0.12 g/dL (95% CI: -0.33, 0.10), confirming the noninferiority of enarodustat to DA. The mean Hb level of each arm was maintained within the target range during the treatment period. Increased total iron-binding capacity and serum iron and decreased hepcidin were observed through week 4 in the enarodustat arm albeit after switching from erythropoiesis-stimulating agents. No apparent safety concerns of enarodustat were observed compared with DA.

DISCUSSION/CONCLUSION

Enarodustat was noninferior to DA for the treatment of anemia in CKD patients receiving maintenance hemodialysis and was generally well tolerated over 24 weeks.

Association between hepatic oxygenation on near-infrared spectroscopy and clinical factors in patients undergoing hemodialysis

The hepato-splanchnic circulation directly influences oxygenation of the abdominal organs and plays an important role in compensating for the blood volume reduction that occurs in the central circulation during hemodialysis (HD) with ultrafiltration. However, the hepato-splanchnic circulation and oxygenation cannot be easily evaluated in the clinical setting of HD therapy. We included 185 HD patients and 15 healthy volunteers as the control group in this study. Before HD, hepatic regional oxygen saturation (rSO2), a marker of hepatic oxygenation reflecting the hepato-splanchnic circulation and oxygenation, was monitored using an INVOS 5100c oxygen saturation monitor. Hepatic rSO2 was significantly lower in patients undergoing HD than in healthy controls (56.4 ± 14.9% vs. 76.2 ± 9.6%, p < 0.001). Multivariable regression analysis showed that hepatic rSO2 was independently associated with body mass index (BMI; standardized coefficient: 0.294), hemoglobin (Hb) level (standardized coefficient: 0.294), a history of cardiovascular disease (standardized coefficient: -0.157), mean blood pressure (BP; standardized coefficient: 0.154), and serum albumin concentration (standardized coefficient: 0.150) in Model 1 via a simple linear regression analysis. In Model 2 using the colloid osmotic pressure (COP) in place of serum albumin concentration, the COP (standardized coefficient: 0.134) was also identified as affecting hepatic rSO2. Basal hepatic oxygenation before HD might be affected by BMI, Hb levels, a history of cardiovascular disease, mean BP, serum albumin concentration, and the COP. Further prospective studies are needed to clarify whether changes in these parameters, including during HD, affect the hepato-splanchnic circulation and oxygenation in HD patients.

Role of circulating endothelial progenitors in responsiveness to erythropoiesis-stimulating agents in hemodialysis patients

Background

Though treatment of anemia in chronic kidney disease (CKD) patients has been improved remarkably by erythropoiesis-stimulating agents (ESA), hypo-responsiveness to ESA poses a persistent problem in a subgroup of CKD patients, especially those on dialysis, with deteriorated mortality or cardiovascular risks. Pathomechanism of this condition including cardiovascular implications has not been sufficiently investigated.

Methods

Clinical parameters of 101 chronic hemodialysis patients which included those hospitalized in our university hospital were examined cross-sectionally. As a marker estimating ESA hypo-responsiveness, erythropoietin resistance index (ERI) was calculated. Numbers of circulating endothelial progenitor cells (EPC) were measured by flow cytometry. Associations among values were analyzed by methods including multiple linear regression.

Results

Majority (93%) of the subjects were hospitalized patients with various comorbidities. ERI (18.4 [7.2–33.0] IU/week/kg/g/dL) and ESA dose (161.6 [75.0–320.9] IU/week/kg) of all the subjects were relatively high. Factors negatively correlated with EPC included age, HD vintage, CRP, pulse rate, ESA dose and ERI, while male sex and systolic blood pressure were positively correlated. By multiple linear regression analysis, age, sex and ERI (standardized coefficient beta − 0.202, p = 0.039) remained as the independently predicting factors of EPC (log CD133/Flk1+ EPC). Darbepoetin alpha was used in 65 patients, especially predominant when requiring higher ESA doses, but by correlation or multivariable analyses, this did not substantially modify the negative association between ERI and EPC.

Conclusions

ERI was independently associated with EPC paucity in a cohort with various comorbidities. This may suggest a link which connects ESA hypo-responsiveness to compromised cardiovascular prognosis of dialysis patients.